Unexpected low power

[Hyperion]

hi
i'm new on this forum (but i lurked it for a long  : )

i'm building an homemade laser with the following items:
-aixiz module with acrylic lens
-SLD1239JL-54 diode bought from stonetek
-ld bought from stonetek

the ld voltage is about 6/7 volts.
i set the ld to give about 193 mah @ 2,6 volts to the diode.
putting a black mouse pad at about 1mm from the diode (without collimating the ray) it burn but in the aixiz module, the spot is veryvery weak  :'(
//img521.imageshack.us/img521/5675/dc080810003ri8.jpg

at 193mah, the output power should be >100mW  :-?

what could be?

 

[MarioMaster]

hi
i'm new on this forum (but i lurked it for a long : )

i'm building an homemade laser with the following items:
-aixiz module with acrylic lens
-SLD1239JL-54 diode bought from stonetek
-ld bought from stonetek

the ld voltage is about 6/7 volts.
i set the ld to give about 193 mah @ 2,6 volts to the diode.
putting a black mouse pad at about 1mm from the diode (without collimating the ray) it burn but in the aixiz module, the spot is veryvery weak :'(
//img521.imageshack.us/img521/5675/dc080810003ri8.jpg

at 193mah, the output power should be >100mW :-?

what could be?

you said you put a mousepad up to the diode and it burned? you probably just got soot and crap all over the glass window on the diode

 

[hydrogenman15]

Sorry, but it's dead and its NEVER coming back.
I think you should watch this < http://www.youtube.com/watch?v=BI7iuBze5I8
Anyways did you check the current? :-?
Is the module getting hot?

--hydro15

 

[Glaserfan]

My guess is that you set the driver current, then soldered the diode and driver together without dishcharging the driver cap. This HAS to be done to prevent the cap disharging into the diode and killing it. Next time make sure to short the LD+ and - terminals for a few seconds before soldering on the diode.

 

[Hyperion]

yes... the diode is dead but i have 4 more diodes
with the first diode i set the driver current before connect the diode many times... so i have killed it  
(a newbie error  : )
then i have solder another diode discharging before the capacitor and it is very bright (and it burn)  

i have another question...
if i want change the current of the driver, must i desolder the diode, change the trimmer and resolder ?

 

[Bionic-Badger]

No, you can change the trim-pot's voltage at any time, even if the laser is powered (though not suggested). If you want to measure the current while the laser is still connected, it's often done by measuring the voltage across a known resistor in the current path.

 

[Hyperion]

great

i set it at 230mah.
now the output power should be around 170mW
the laser burn very well

phr-803t is coming... :

thanks to all

 

[GooeyGus]

Normally I'm not too nit-picky, but I just have to point this out

You're using the term "mAh" which is usually used as a capacity rating for batteries. For example, 1000mAh would mean that the battery is capable of putting out 1000mA for one hour.

So when you say you're setting the diode at "230mAh" it really should just be "230mA" as mA is the measurement for current whereas mAh is current over time

 

[Hyperion]

yesyesyes i knew it
sorry thanks

 

[kubbur]

good video there